I took my iZip Via Rapido out for the first time on a crisp morning under a bright winter sun, making my way to the office on the Goose Creek Path in Boulder, Colorado. The wide, paved route, like the city’s other bicycle trails, winds through town and makes you glad to be going to work, or anywhere, at least for a few moments, as you roll over and under roads and alongside trees and streams instead of cars and buses. The e-bike’s quiet electric hum did nothing to diminish the path’s appeal. The bright-red Rapido surged to its top speed of 20 mph as I effortlessly turned the pedals, and I idly wondered whether this is what taking EPO feels like.

Although I hadn’t been sure what to expect of the bike, I wasn’t ­surprised to be grinning. I’m plenty fit, but I’m not one to deprive myself of indulgences. When I run the Bolder Boulder, a 10K race, I stop for the Slip ’n Slide halfway into the course. Once, in New Zealand, I took a helicopter up a mountain, then rode downhill—talk about no pain, all gain. Now, zipping along , I felt sneaky, like when I gave my wife my anvil of a Gary Fisher so I could ride an Ellsworth.

I’d come to own the Rapido almost accidentally. The bike was part of a silent auction at a fund-raiser for an orphanage in post-earthquake Haiti. While party-goers overbid on dance lessons and ski condos, they ignored the gleaming two-wheeler parked in the hall. I put down my mojito (sales tip for bike shops: serve drinks) and made the minimum bid—$500, about a third of the sticker price—and went to spread the word. I didn’t need the bike. I pedaled to the office on a Specialized cruiser at an easygoing 10 miles per hour, feeling the breeze and watching for prairie dogs. Surely an elderly cyclist, someone with the desire but not the stamina, would raise me by 10 bucks and ride away with the deal of the night.

But no. In my besotted state I overlooked the fact that in Boulder, you could probably do better selling bikes that are harder to pedal. This is a town where athletes over 60, if they make any concession at all, may grudgingly increase their recovery period between centuries. At the office, none of my coworkers—who I sometimes accompany on the type of grueling lunch rides that readers of this magazine would recognize, even if I’m not truly a part of their spandex-clad culture—lined up to give the Rapido a try. In fact, they may have been surprised that Boulder hadn’t banned electric bikes in the same way San Francisco outlawed Happy Meals.

I had no such hang-ups, at least not at first. Then one day the Rapido’s battery died—who remembers to plug in a bike?—and instead of cutting my commute in half, the 52-pounder doubled it. Plugging the bike in left me unsettled: I disliked tapping into the grid for something I could do on my own power. Plus, I missed the prairie dogs. The next day, I rode the Specialized, and I rode it slow.

For a few weeks the iZip disappeared into the corner of the garage, next to the Adams tandem tagalong we don’t use anymore because the kids all ride their own bikes. Bikes they have to pedal, sometimes hard, the way God—and Edoardo Bianchi—intended.

The e-bike might have started to collect cobwebs. But then came a spring day and a dilemma. I needed to get across town in the ­afternoon to coach my son’s soccer team, then race back to the office. I stood in the garage, looking back and forth from the cruiser (take me, take me, you’ll be late but happy) to the e-bike (come on, your time is precious, right?). I succumbed to expediency and saddled up the Rapido. The bike delivered me everywhere on time without having to resort to climbing into a car.

I’ll never give up the cruiser. But what won me over about the Rapido that day wasn’t the convenience, or that it allowed me to avoid the car, or a contrarian delight I may have taken in riding an e-bike in Boulder. No, it was the moment I found myself behind a cyclist on a training ride—the kind who normally flashes by when I’m puttering along. Without thinking, I cranked the throttle and whizzed past him while barely turning the pedals. I felt a pang of remorse for giving in to the impulse—but then something else, something like the way you feel on a Slip ­’n Slide detour in the ­middle of a 10K. Something like glee. If you can’t enjoy a little guilty pleasure, you really shouldn’t own an electric bike to begin with.